Why is it important to use a reaction with a high atom economy?

Answer: Use own words

Atom economy. The atom economy of a chemical reaction is a measure of the percentage of reactants that become useful products ... Efficient processes have high atom economies, and are important for sustainable development, as they use fewer natural resources and create less waste.

Explanation:

What is a good atom economy?

Atom economy (atom efficiency) is the conversion efficiency of a chemical process in terms of all atoms involved and the desired products produced. Atom economy is an important concept of green chemistry philosophy, and one of the most widely used metrics for measuring the "greenness" of a process or synthesis.